Definition
Q235 steel is a plain carbon structural steel which is widely used in China, Q235 material in Chinese standard GB/T 700 is divided into 4 quality grades: Q235A, Q235B, Q235C and Q235D; Density of this steel is 7.85 g/cm3, tensile strength is 370-500 MPa; yield strength is 235 MPa (data are for steel bar or steel plate diameter≤16mm). Since it’s mild steel, it is used directly without heat treatment.
Meaning and Designation “Q” is the first letter of Chinese splling of “Qu Fu Dian”, which means Yield Point. “235” refers to the minimum yield strength 235 MPa tested with steel diameter≤ 16mm.
Features
Q235 steel has good plasticity, toughness and weldability, as well as a certain strength, good cold bending performance. Q235 material is usually rolled into wire rod or round steel, square steel, flat steel, angle steel, | beam, channel steel, other sections and steel plates.
Applications
These products are widely used in construction and engineering welded structures, to make steel bars or build factory buildings, high voltage transmission towers, bridges, vehicles, boilers, containers, etc., and also used as a mechanical part with less demanding performance such as less stressed rods, connecting rods, screws, nuts, ferrules, brackets, and stands, etc. opted by ASTM in the United States.
Steel Standard | Steel Grade | Chemical Composition | |||||
---|---|---|---|---|---|---|---|
C(≤) | Mn(≤) | Si(≤) | S(≤) | P(≤) | Cu(≤) | ||
ASTM | A36 | 0.26 | 0.40 | 0.050 | 0.040 | 0.2min | |
GB | Q235A | 0.14~0.22 | 0.3~0.65 | 0.30 | 0.050 | 0.045 | |
GB | Q235B | 0.12~0.20 | 0.30~0.70 | 0.30 | 0.045 | 0.045 | |
JIS | SS400 | – | – | 0.050 | 0.050 |
What is Q235 steel grade?
similar to Q235B steel plate, it is one Q235b equivalent steel standard, another one is SS400. While the difference between A36 and Q235B is as follows:
- Different Yield Point (A36=250MPa, Q235B=235MPa);
- Different Tensile Strength (A36=400-550MPa, Q235B=375-500MPa);
- Different element content requirements: (A36: C is equal to or less than 0.25%, Si is less than or equal to 0.4%, P < 0.04%, s is less than or equal to 0.05%; Q235B:C=0.12-0.2%, Si is less than or equal to 0.3, P < 0.045%, s is equal to or less than 0.045%).Q235 manganese content of the requirements (Mn=0.30-0.70%) A36 manganese content is not required.